From: Naoya Horiguchi Date: Thu, 28 Jul 2016 22:48:38 +0000 (-0700) Subject: mm: hwpoison: remove incorrect comments X-Git-Tag: v4.14-rc1~2792^2~18 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=7c7fd82556c61113b6327c9696b347a82b215072;p=platform%2Fkernel%2Flinux-rpi.git mm: hwpoison: remove incorrect comments dequeue_hwpoisoned_huge_page() can be called without page lock hold, so let's remove incorrect comment. The reason why the page lock is not really needed is that dequeue_hwpoisoned_huge_page() checks page_huge_active() inside hugetlb_lock, which allows us to avoid trying to dequeue a hugepage that are just allocated but not linked to active list yet, even without taking page lock. Link: http://lkml.kernel.org/r/20160720092901.GA15995@www9186uo.sakura.ne.jp Signed-off-by: Naoya Horiguchi Reported-by: Zhan Chen Acked-by: Michal Hocko Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/mm/hugetlb.c b/mm/hugetlb.c index abc1c5f..213ff90 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -4391,7 +4391,6 @@ follow_huge_pud(struct mm_struct *mm, unsigned long address, /* * This function is called from memory failure code. - * Assume the caller holds page lock of the head page. */ int dequeue_hwpoisoned_huge_page(struct page *hpage) { diff --git a/mm/memory-failure.c b/mm/memory-failure.c index 11de752..de88f33 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -741,8 +741,6 @@ static int me_huge_page(struct page *p, unsigned long pfn) * page->lru because it can be used in other hugepage operations, * such as __unmap_hugepage_range() and gather_surplus_pages(). * So instead we use page_mapping() and PageAnon(). - * We assume that this function is called with page lock held, - * so there is no race between isolation and mapping/unmapping. */ if (!(page_mapping(hpage) || PageAnon(hpage))) { res = dequeue_hwpoisoned_huge_page(hpage);